The Early Warning and Response System for communicable diseases in the EU: an overview from 1999 to 2005

Citation style for this article: The Early Warning and Response System for communicable diseases in the EU: an overview from 1999 to 2005. Euro Surveill. 2006;11(12):pii=666. Available online: http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=666
Date of submission:

Under Decision 2119/98/EC of the European Parliament
and of the Council, a network for epidemiological surveillance and control
of communicable diseases in the Community was set up in 1998. One pillar
of Decision 2119/98/EC is the early warning and response system (EWRS).
The main objective of the network is to establish permanent communication
between European Union (EU) Member States’ public health authorities,
which are responsible for determining the measures required to control
communicable disease-related events. Since 1998, a web based informatics
tool has been developed in order to allow information to be shared between
the relevant public health authorities. Between 1998 and December 2005,
a total of 583 messages were circulated through the EWRS, notifying 396
events. The information shared through the system helped to coordinate
public health measures in the EU. However, only few events prompted specific
measures at Community level and most of them were controlled with public
health measures applied at national level. Major events (such as the
Severe Acute Respiratory Syndrome) and the results of simulation exercises
prompted the Commission to upgrade the informatics system on the basis
of user needs. Since 1 May 2004 the 10 newest Member States have provided
information under the current legislation and since April 2005 the European
Centre for Disease Prevention and Control (ECDC) is part of the system.
Future developments will include a link between the existing EWRS and
the communication platform currently developed by the ECDC.

Introduction

The emergence of SARS in 2003 clearly demonstrated how a previously
unknown disease could spread rapidly, causing high mortality and morbidity.
Fast travel and global trade facilitated transmission in the absence
of relevant vaccines and drugs. Effective counter-measures were applied,
but the event underlines the need for worldwide cooperation to control
such contingencies. Early detection of cases and efficient international
communication and coordination was an advantage to tackle the epidemic.
Public health measures undertaken not only by the affected countries
but by the entire international community, with the support and guidance
of the World Health Organization (WHO), helped to prevent catastrophic
developments. Coordination in the European Union based on the EWRS contributed
to Member States’ knowledge of the situation and their readiness
to stem any potential spread of the disease.

The threat of a pandemic influenza is currently prompting governments
and international bodies with responsibilities in public health protection
to address preparedness plans that could mitigate the potential effects
of a pandemic, and to reinforce policies, contingency plans and resources,
including the alert systems and their networks (1, 2).

The tools for European coordination to tackle communicable disease health
threats must enable the key players to obtain and share key information
on public health measures, both quickly and securely. The key players
engaged in this process are the national health authorities, the national
public health agencies, the Ministries for Health in Member States, and
the European Commission and its agencies, in particular the ECDC.

The main objective of the paper is to outline the interactions of the
EWRS key players and to describe the alert system for communicable diseases
currently in place in the EU. It refers to the existing legal basis,
the functioning of the system, the main players concerned with operations
since its introduction, and the most recent upgrade undertaken on the
basis of lessons learned from the past experience.
The legal basis

Decision 2119/98/EC established the early warning and response system
as one of the two pillars of the Community network for the epidemiological
surveillance and control of communicable diseases. The other pillar of
the Community network is the base for the epidemiological surveillance
in the EU and is made up by establishing permanent communication between
the Commission and those structures which, at Member State level and
under the responsibility of each Member State, are competent at national
level and are charged with collecting information relating to the epidemiological
surveillance of communicable diseases. The early warning and response
function allows information exchange, consultation and coordination at
Community level, should an event due to communicable diseases endanger
public health at Community level. The network brings into communication
the European Commission and the competent public health authorities in
Member States responsible for determining the measures which may be required
to protect public health against communicable disease threats. The system
links the European Commission, the 25 Member States, Bulgaria and Romania
and the European Economic Area (EEA) countries (Iceland, Liechtenstein
and Norway). The ECDC has had access to EWRS since its establishment
in May 2005 (3).

Under Decision 2119/98/EC, authorities communicate i) information regarding
the appearance or resurgence of cases of communicable diseases, together
with information on control measures applied; ii) any relevant information
concerning progression of epidemic situations; iii) information on unusual
epidemic phenomena or new communicable diseases of unknown origin, including
in non-member countries; iv) information concerning existing and proposed
mechanisms and procedures for the prevention and control of communicable
diseases, in particular in emergency situations; and v) any information
which could help Member States to coordinate their efforts for the prevention
and control of communicable diseases, including any counter measures
implemented (Art. 4, Decision 2119/98/EC)(3). This kind of information
is provided through an informatics tool developed expressly for this
purpose.

Decision 2000/57/EC states that the EWRS is reserved for events that
have ‘Community relevance’. These events are: i) outbreaks
of communicable diseases extending to more than one Member State of the
Community; ii) spatial or temporal clustering of cases of disease of
a similar type, if pathogenic agents are a possible cause and there is
a risk of propagation between Member States within the Community; iii)
spatial or temporal clustering of cases of disease of a similar type
outside the Community, if pathogenic agents are a possible cause and
there is a risk of propagation to the Community; and iv) the appearance
or resurgence of a communicable disease or an infectious agent which
may require timely, coordinated Community action to contain it (Art 1
and annex I, Decision 2000/57/EC) (4). The procedures for information,
consultation and cooperation under the EWRS are described in article
2 of Decision 2000/57/EC. Three levels of consultation are defined: level
1 for information exchange, level 2 for notification of a potential threat
and level 3 for definite threat (Annex II, Section 1,2,3, Decision 2000/57/EC)(2).
A specific procedure for information to the general public and concerned
professional is reported in section 4 of annex II of Decision 2000/57/EC
and states that Member States shall provide suitable information to concerned
professional and the general public and shall inform them of the measures
adopted and that the Commission and Member States shall inform of any
guidance agreed at Community level and when the public health is over
(4).

Should one or more of the previously mentioned circumstances occur,
Member States shall, on the basis of the information available, consult
each other in liaison with the Commission with a view to coordinate their
actions. In particular, where a Member State intends to adopt, as a matter
of urgency, control measures in response to the appearance of a communicable
disease, it shall, as soon as possible, inform the Commission and the
other Member States. On the basis of this consultation and of the information
provided Member States shall coordinate in liaison with the Commission
the measures which they have adopted or intend to adopt at national level
(Art 6 Decision 2119/98/EC)(3).

Each Member State designates the structure and/or the authorities referred
to the early warning and response function and notifies the Commission
and the other Member States (Art 9, 2119/98/EC). The public health authorities
which have been formally designated represent the network of the contact
points of the EWRS (3).

Description of the informatics tool currently available to implement
the early warning and response under Decisions 2119/98/EC and 2000/57/EC

Since Decision 2119/98/EC entered into force, an informatics tool has
provided the platform for communicating information. The tool currently
linking the EWRS contact points is a web-based system. The access to
the system is secured and is limited to the formally appointed contact
points. As previously mentioned, following notification from Member States,
the contact point receives a login and a password from the Commission
to access the system, and full authorisation to write and read messages.
When a message is posted on the system, it is automatically circulated
to all EWRS contact points, and the network (Commission, Member States,
acceding and the EEA countries, and ECDC) is informed at the same time
of how the situation is progressing and of the measures planned or undertaken
at national level to respond to the specific event.

On the basis of lessons learnt from past events, mainly from the SARS
epidemic, and on the basis of the recommendations made in the report
of the EWRS activities for the years 2002 and 2003 (3), there has been
a complete technological overhaul of the system. The new EWRS application
was launched in May 2004 and it is currently in use. Additional modifications
of specific functions were introduced after the 2005 simulation exercises
(6).

In the current application, a single message can contain a text of up
to 3999 characters, and additional comments up to 1999 characters may
be added. There is no limit to the number of comments that can be made
following a single message. Additional documents, for a maximum of 9
Megabytes, can be attached to messages and comments. Readability and
classification of the comments has been also improved. A few ‘simple
search’ features were also added to the ‘threat listing’ page
to select important flags (message content, syndrome/disease, pathogen,
reporting reason, and country of occurrence). After rebuilding the core
of the application, a calendar function was added to create a meeting
agenda and to facilitate the sharing of working documents among users
without overloading the core messages. To prevent the risk of overload
of messages, should a specific event require a large number of notifications,
a ‘follow up’ section was added. A new messaging system was
also introduced in May 2005 (selective messaging) that allows participants
to send a message to selected recipients. The European Commission is
always notified of ‘selective’ messages. The user levels
were expanded to give access both to the ECDC and the WHO. The WHO has,
with the agreement of Member States, a read-only access to the system.
Other security enhancements were also added.

A short message service (SMS) messaging function has been activated
in order to transmit to the European Commission Officer on duty real
time notification that a message has been posted on the system.

In addition to these function the system is linked to the Medical Intelligence
System (MedISys) (7). MedISys is a piece of software that browses the
web every 20 minutes in order to find articles, documents and latest
news about health matters. About 350 keywords are currently used and
1200 websites are visited. Access to the system has been granted to Ministries
of Health, national surveillance institutes, specific EU supported projects,
ECDC and WHO. Graphs, statistics and world maps allow a quick identification
of threats and localisation of the events. The system is based on the
European Media Monitor, which is freely accessible to all (8).

The ECDC was officially established in May 2005, but started activities
in March 2005. As the assistance of Commission by the ECDC in operating
the EWRS is stated in the ECDC founding regulation, the agency was rapidly
integrated into all EWRS related activities (9). The ECDC has been connected
to the EWRS since April 2005. ECDC has implemented its threat monitoring
mandate using the EWRS messages as a source of information on threats
in Europe, complemented by an active search of additional formal and
informal sources.

The EWRS operations

Since Decision 2119/98 entered into force at the end of December 2005,
a total of 583 messages have been circulated through the EWRS. These
messages notified a total of 396 events. The first message (about legionellosis)
was posted on 30 November 1998 and no further messages were posted in
1998. Figure 1 reports the number of the events notified through the
EWRS from January 1999 to December 2005, including the level of activation
as defined by procedures reported in annex II of Decision 2000/57/EC
(4).

The nature of the events (diseases and/or syndromes) notified during
the same period 1999-2005 is reported in Table 1. The trend of the diseases
and syndromes which have been reported at least five times in one year
(haemorrhagic fever, salmonellosis, meningitis, influenza, SARS and measles)
is reported in Figure 2. Only a few events have prompted specific measures
at Community level; most were controlled by applying public health measures
at national level. Events which required a more complex response, involving
coordination of measures and contacts between health authorities in Member
States, are summarised in Table 2. Comments were added to the majority
(around two thirds) of these events. Details concerning the specific
events reported in the Table are available in the annual reports of the
EWRS (5, 10).

The SARS epidemic dominated the EWRS activity from March to June 2003.
Figures on EWRS activities during this period are reported in Table
3 and Figure 3. The system provided a unique tool to circulate reliable
information quickly to the Commission and to the Member States. During
the first phase of the event in particular, the EWRS was able to pick
up a notification posted by France on 11 March 2003 about a real and
serious threat in Vietnam. The content of messages circulated during
the SARS outbreak can mostly be put under two categories. The first
category is reports of measures undertaken by Member States to control
the spread of SARS, and it provided very useful information which helped
to coordinate the response to SARS at national and at EU level (Table
3). The second category is case and update reports, which provided
useful and additional information to Member States when weighing the
impact of imported cases in the EU. This second set of information
was consistent with the WHO notifications. The nature and magnitude
of the event caused a huge and rapid flow of messages. Starting from
the second week of the outbreak, this situation caused an overload
of the EWRS mailbox and had a negative impact on processing and interpreting
data and on control activities (5). The problem was solved by creating
a specifically dedicated mailbox for selected messages (case and update
reports, official communications, call for meetings and consultation
teleconferences, etc.). These elements provided the basis for the upgrading
of the system (5, 10).

Discussion

The European collaboration on communicable diseases only started recently,
within the context of the public health framework set out in the Commission
Communication of 24 November 1993 on the framework for action in the
field of public health. The network for the epidemiological surveillance
and control of communicable diseases in the Community with its early
warning and response function operating under Decisions 2119/98/EC
and 2000/57/EC has been one of the most successful public health instruments.

The EWRS is being used more and more frequently to share relevant
information between the Member States, the Commission and the ECDC.
The system currently available is a unique tool that helps to coordinate
public health measures intended to control communicable diseases threats
in the EU. The increased number of messages circulated through the
EWRS mirrors the efforts done in implementing the current EU legislation
on communicable diseases, and also shows the value of such an instrument
for appropriate communication between partners.

Although the EWRS is not intended to be a tool to monitor communicable
diseases in the EU, analysis of events notified since 1999 tells us
about the nature and frequency of the threats which required a response
at Community level. The knowledge of these figures can help Member
States, the Commission and the ECDC to strengthen mechanisms and actions
and thereby to be better prepared to respond to specific events and
to predict, at least in part, what we can expect at short and medium
term.

A/H5N1 related events were the most frequent cause of notification
in 2004 (21 events) and the second most frequent in 2005 (13 events).
Sharing information encouraged a tangible effort to coordinate measures
for strengthening preparedness to respond to the potential progression
of the pandemic alert phases. The Member States were regularly informed
through the EWRS about the measures undertaken at national level and
a consistent response was reached at Community level (for the most
part, monitoring the situation, implementing active surveillance, advising
EU citizens travelling to and from affected areas, strengthening synergies
with veterinary services, and finalising pandemic plans).

Unpredictable incidents represent a significant proportion of notified
events. The system proved to be a unique tool to circulate reliable
information, not only during the unforeseen SARS epidemic, which dominated
the EWRS activities from March to May 2003, but also during one-off
incidents which required the rapid implementation of public health
measures, such as, the event related to the rabid dog illegally imported
into the EU that bit or had close contact with several EU citizens,
and the incident linked to erroneously distributed samples of live
influenza virus A/H2N2 to carry out proficiency testing (Table 2).

Further analysis by the Commission, Member States and the ECDC of
the reported events through the EWRS and of the public health responses
in term of measures planned and undertaken in response to the notified
threats will be essential to better understand and to strengthen the
capacity to efficiently tackle communicable diseases in the EU.

All events that required urgent notifications and a more complex response
and coordination of measures (Table 2) were notified without delay,
demonstrating a clear improvement after 2003 (5). These events were
a significant test of the usefulness of the EWRS. The system fulfilled
its institutional role by circulating messages in a timely fashion
among the EWRS contact points in Member States, by providing shared
positions among the national public health authorities, and by facilitating
the exchange of information on specific issues. The consultation platform
provided by EWRS was very much appreciated by the authorities of the
Member States and resulted in consistent national decision making for
the control of these events.

The analysis of the content of activation level 1 messages (which
include information messages) demonstrates that a number of them still
remain focused on risk assessment issues and that a large part deals
with requests for information about similar events identified in other
Member States. The integration of specific functions of the current
EWRS informatics tool in the communication platform that ECDC is developing
will be instrumental to focus the use of the system to cover those
circumstances as laid down in Decisions 2119/98/EC and 2000/57/EC.

The integration of the 10 new Member States in the EWRS was a special
challenge. New Member States made efficient use of the EWRS, demonstrating
a level of activity comparable to that of the old Member States. Since
accession in May 2004 the 10 new Member States have had full access
to the EWRS and have made active use of the system both to notify new
events and to follow up with comments events been notified by other
Member States or by the Commission. A recent analysis prepared by the
ECDC, covering the period from June until December 2005, demonstrates
that the amount of threats notified through EWRS is comparable for
old and new MS (after adjustment for population), showing good integration
of new MS in the EU alert system for communicable diseases (11).

EWRS was the communication tool used during the simulation exercise
'Common Ground' that was conducted by the UK’s Health Protection
Agency (HPA) as a command post exercise on 23 to 24 November 2005.
This exercise was the second of two EU exercises commissioned by the
European Commission to evaluate the ability and capabilities of Member
States to respond to a health-related crisis, in this case an influenza
pandemic. EWRS was made available for the exercise to all 25 Member
States plus Norway, Iceland and Switzerland. Despite heavy use during
the exercise (437 messages circulated, an average of nearly 10 messages
per hour, and 3672 responses), the system performed efficiently and
no breakdown was registered. Nevertheless, given the nature of the
simulation, there was considerable overload and heavy traffic, and
users rapidly became overwhelmed by the huge number of messages. As
the EWRS was the only system for simultaneous European communication
available, participants used it for all sorts of information exchange,
although the system was only developed, as laid down in Community legislation,
for official notification of measures and their coordination. As previously
mentioned, the future communication platform developed by the ECDC
will be also important for strengthening information sharing during
emergency situations like those simulated during EU-wide exercises.

The EWRS should also be considered in the perspective of the future
implementation of the revised International Health Regulations (IHR)
(12, 13). IHR will enter into force on 15 June 2007, and require gradual
implementation, to be completed by 2016 at the latest. Close coordination
between the Commission and Member States will help to optimise their
implementation, and better protect EU citizens from public health emergencies
due to communicable diseases. In particular the ECDC and the EWRS will
be instrumental to help the implementation process of IHR in a stronger
and more coherent way (12, 13).

2. Communication from the Commission to the Council, the European Parliament,
the European Economic and Social Committee and the Committee of the Regions
on strengthening coordination on generic preparedness planning for public
health emergencies at EU level. Bruxelles, 28.11.2005, COM (2005) 605
Final.http://eur-lex.europa.eu/LexUriServ/site/en/com/2005/com2005_0605en01.pdf

4. Commission Decision of 22 December 1999 on the early warning and
response system for the prevention and control of communicable diseases
under Decision No 2119/98/EC of the European Parliament and of the Council.
(Notified under document number C(1999) 4016)(2000/57/EC). Official Journal
of the European Communities 26.01.2000 L 21.http://eur-lex.europa.eu/pri/en/oj/dat/2000/l_021/l_02120000126en00320035.pdf

5. Report from the Commission to the Council and the European Parliament.
Report on the operation of the Early Warning and Response System of the
Community Network for the Epidemiological Surveillance and Control of
Communicable Diseases (Decision 2000/57/EC) during 2002 and 2003. Bruxelles,
29.03.2005 SEC (2005) 394.http://eur-lex.europa.eu/LexUriServ/site/en/com/2005/com2005_0104en01.pdf

10. Report from the Commission to the Council and the European Parliament.
Report on the operation of the Early Warning and Response System of the
Community Network for the Epidemiological Surveillance and Control of
Communicable Diseases (Decision 2000/57/EC) during 2004 and 2005. In
press.

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